Northern Nigeria is one of the few regions in the world where polio remains endemic, despite efforts to eradicate this crippling and potentially fatal virus. Sarah Simpson reports from the north's largest city, Kano, where polio victims have joined the fight against polio by using their disabilities to shock reluctant parents into getting their kids immunized.

Aminu Ahmed and three other members of the Polio Victims Trust Association of Kano climb into a specially adapted taxi. All of the men are crippled by polio, including the driver. They are on their way to a poor part of town where many parents had rejected a polio vaccination for their children, that is, until the association members intervened.

"Before they [were] not accepting, but now they are accepting, because we show them, 'Do you want your son or your family to be like me?' Most of the people say 'I do not like it,' so we say OK, [allow] your son to be immunized,'" he said.

The men must leave the car, because it cannot pass through Kano's old town, a maze of narrow alleyways and high mud walls. Ahmed leads the way. Both his legs are withered by polio, which he contracted as a child, so he moves across the ground on his hands and one foot.

Ahmed has visited many families in this cloistered neighborhood to urge parents to heed the advice of health workers. One mother, Safiya Ado, has three boys all under the age of six.

Speaking in Hausa, Ado explains that, despite her initial skepticism, she now fully cooperates with health workers. She is heard here through an interpreter.

"Because I want my children to grow very well and I do not want them to be polio victims, I give them over to health workers every month when they visit," she said.

Residents like Ado became distrustful of a World Health Organization (WHO) campaign to eradicate polio when Muslim religious leaders voiced doubt over the safety of the vaccine. They said that it was a Western plot to reduce fertility levels in Muslim children.

That was back in 2003 and led to an abrupt halt in a W.H.O. anti-polio program that consisted of administering two drops of polio vaccine onto the tongues of 4 million children in Kano State.

Concerns spread, and ultimately five northern Nigerian states banned the polio vaccine altogether.

The number of polio cases in northern Nigeria has since spiked. In 2006, Nigeria accounted for 70 percent of the world's cases of polio, according to WHO figures.

Though religious and political leaders now support polio immunization, Mohammed Doko of the charity COMPASS (which is working closely with the polio victims in Kano) says it is still difficult for aid workers like him to give the assurances parents need because of years of mixed messages.

"You know, this is a relatively conservative society down here and anything from the West is taken with a little caution on the side of the families," he said.

But acceptance of the polio immunization program is on the rise in Kano, agree health workers and community leaders. In part that is because the program has been broadened to cover a variety of diseases and mosquito nets are also distributed to tackle malaria, making the program more palatable. But Kano's polio victims have also played an important role in getting the right message across, says Doko.

"Most polio victims are from here," he added. "The people here identify with them, they know them. So they accept messages coming from them. And especially seeing them crawling on the ground has a very deep impact on parents."

Nigeria is one of only six countries in the world classified as polio endemic by WHO. A 20-year-old global initiative to eradicate polio missed a 2005 deadline, though WHO officials in Geneva last month said that polio eradication remained a priority without setting a new target date.